Reservoir fluid samples may be needed for a variety of reasons. Reservoir fluid samples may be taken from a subterranean formation and then analyzed to establish their physical and chemical properties, such as hydrocarbon type and pressure, volume and temperature (PVT) behavior of the reserves in place. These properties may help in planning efficient extraction of the hydrocarbons. A set of measurements performed on a fluid sample from a hydrocarbon reservoir may include PVT relationships, viscosity, composition, gas/oil ratio (GOR), differential vaporization, and multistage separation tests. Fluid samples may also provide information needed to aid in planning and special treatments that may be required for production, such as hydrogen sulfide removal, waxing tendencies, asphaltene content, metallurgy and refining trials. Asphaltene precipitation may produce tar-like solids that may come out of suspension in crude oil when pressure is reduced within the formation, in production tubing and in surface facilities. Therefore, asphaltene content may be an important parameter in choosing optimal completion designs.
The fluid samples may be taken by formation testing tools and placed into sample cylinders of the formation testing tool. Standard un-cushioned wireline sample chambers may risk phase change as the temperature of the system changes. Although, the integrity of the sample may be checked at surface, and once again at the laboratory prior to opening, the integrity of the sample may not currently be checked at ocean floor conditions or during transport to the laboratory. Also, although nitrogen cushioned cylinders may be more resistant to phase change, for low GOR high pressure samples, such as found in the turbidite sands of the Gulf of Mexico, maintaining single phase may not be guaranteed. Additionally, although the integrity of the sample may be checked at single points at surface, and the laboratory, often the sample is not quality controlled (“QC”).